Hi, Linda,
If your conversion goes smoothly--and Microsoft had designed and tested for all situations🙄--you should automatically see your contacts in the new Outlook, regardless of whether you are running Windows 10 or 11 and regardless of whether you were using the Mail desktop app or Microsoft Office Suite's Outlook (desktop app) to manage your mail and contacts.
Were you running the Mail app on a PC to manage your contacts before the conversion? If so, then do check that you have granted permission to view your contacts as I posted toward the bottom of page 4 of this thread. Don't worry, it's just a setting checkbox that doesn't delete any personal data.
If you were using MS Office's Outlook on your desktop, do the same check for that app.
If you were using Outlook strictly on the Web, the change should have been automatic. Desktop app permission settings will have no impact.
Contacts are actually stored on the Microsoft server, so they're not lost, just invisible to your new (web-based) Outlook. There is no need to re-enter them. So, if you still cannot see them after checking permission settings, I suggest requesting a callback from Microsoft Support. They can make whatever adjustments are necessary on the server-side to ensure the contacts are visible.
Note: you will need to wade through several off-putting irrelevant FAQs (and maybe an AI chat-bot🙄) first, but eventually you will get to a prompt asking if you would like a callback. It costs you nothing but time. Also, you do not need to allow them remote access to your PC, as the fix is done server-side. Just be insistent.
Best of luck!🤞
LostInSpace88